Nizar A. Khamjan

Dr. Nizar A. Khamjan

orcid

Research Focus & Metrics

Academic Career Length

6Years (2021-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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21 November 2022 in Neurochemical Research
Verified
Journal Article
Closed access
PDF file
HAHayder Al-kuraishy
Hayder Al-kuraishy
AAAli I. Al-Gareeb
Ali I. Al-Gareeb
AAAbdulrahman Alsayegh
Abdulrahman Alsayegh
ZHZaki H Hakami
Zaki H Hakami
NKNizar A. Khamjan
Nizar A. Khamjan
Michel De WaardMichel De Waard
Michel De Waard

12 June 2023 in Vaccines
Verified
Journal Article
Open access
PDF file
NKNizar A. Khamjan
Nizar A. Khamjan
MLMohtashim Lohani
Mohtashim Lohani
MKMohd Faheem Khan
Mohd Faheem Khan
SKSaif Khan
Saif Khan
AAAbdullah Algaissi
Abdullah Algaissi
Currently available COVID vaccines are effective in reducing mortality and severity but do not prevent transmission of the virus or reinfection by the emerging SARS-CoV-2 variants. There is an obvious need for better and longer-lasting effective vaccines for various prevailing strains and the evolving SARS-CoV-2 virus, necessitating the development of a broad-spectrum vaccine that can be used to prevent infection by reducing both the transmission rate and re-infection. During the initial phases of SARS-CoV-2 infection, the nucleocapsid (N) protein is one of the most abundantly expressed proteins. Additionally, it has been identified as the most immunogenic protein of SARS-CoV-2. In this study, state-of-the-art bioinformatics techniques have been exploited to design novel multiple epitope vaccines using conserved regions of N proteins from prevalent strains of SARS-CoV-2 for the prediction of B- and T-cell epitopes. These epitopes were sorted based on their immunogenicity, antigenicity score, and toxicity. The most effective multi-epitope construct with possible immunogenic properties was created using epitope combinations. EAAAK, AAY, and GPGPG were used as linkers to connect epitopes. The developed vaccines have shown positive results in terms of overall population coverage and stimulation of the immune response. Potential expression of the chimeric protein construct was detected after it was cloned into the Pet28a/Cas9-cys vector for expression screening in Escherichia coli. The developed vaccine performed well in computer-based immune response simulation and covered a diverse allelic population worldwide. These computational findings are very encouraging for the further testing of our candidate vaccine, which could eventually aid in the control and prevention of SARS-CoV-2 infections globally.

26 June 2023 in Journal of Infection and Public Health
Verified
Journal Article
Open access
NKNizar A. Khamjan
Nizar A. Khamjan
SBSaba Beigh
Saba Beigh
AAAbdullah Algaissi
Abdullah Algaissi
KMKanu Megha
Kanu Megha
MLMohtashim Lohani
Mohtashim Lohani
SDSajad Ahmad Dar
Sajad Ahmad Dar
Except for a few preventative Human Papillomavirus (HPV) vaccines, there is currently no cure for HPV infection. There are a number of cutting-edge strategies and potent medications or herbal formulations that can be applied topically for early clearance of HPV infection before HPV DNA gets integrated into host cell genome. This is facilitated due to cervical cancer having distinct and well-recognized long precancerous stages. This review aims to outline every possible medication and formulation, both natural and synthetic, that can be applied topically as intravaginal application to help remove HPV infection at an early precancerous stage. Several anti-HPV/HPV clearance compounds and formulations for high-grade lesions are undergoing clinical trials. However, the majority of compounds are still in the early stages of development and require additional research to become viable HPV clearance candidates. Synthetic drugs may be more promising because they may have a more targeted effect; however, they may also have significant adverse effects. On the other hand, natural medications are safer to use. They are less specific, but have minimal to no adverse effects. This article may serve as a valuable resource of information for managing and preventing precancerous carcinogenic HPV infections. Research could be directed toward developing candidate drugs to make evidence-based decisions about advancing them to clinical trials and, eventually, to the market for potential use in the prevention and control of cervical cancer, which is almost always preventable or even curable if detected early.

AAAbdulaziz Alhazmi
Abdulaziz Alhazmi
EAEDROUS ALAMER
EDROUS ALAMER
SASiddig Ibrahim Abdelwahab
Siddig Ibrahim Abdelwahab
NKNizar A. Khamjan
Nizar A. Khamjan
AHAbdullah Hamami
Abdullah Hamami
AAAbdullah Algaissi
Abdullah Algaissi
Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) continues to spread globally, causing unprecedented effects on global health and economies. Community-based serological data are essential for understanding the true prevalence of infections, specifically the subclinical infections, as COVID-19 asymptomatic infections are common. Such data would also be important for decision making around choosing appropriate epidemiological control measures, as well as for the true estimation of mortality rates in the population. Further, determining the seroprevalence of anti-SARS-CoV-2 antibodies in the population would provide important information on herd immunity. In this study, we conducted a population-based age-stratified serological study to understand the prevalence of SARS-CoV-2 in Jazan Province, Saudi Arabia. Out of 594 participants who were recruited from 29 August to 30 December 2020, just before the vaccination rollout program in Saudi Arabia, about 157 were seropositive for SARS-CoV-2, indicating an estimated seropositivity rate of 26%. Although no significant difference in seropositivity was seen between male and female participants, we found that lower seroprevalence was associated with the younger (below 18 years old) and older populations (older than 56 years) compared with other age groups (19–55 years). These data indicate a high prevalence of SARS-CoV-2 antibodies following the peak of COVID-19 spread in Jazan province; however, most of the population (three-quarters) remains susceptible to SARS-CoV-2 infection.

25 August 2023 in Heliyon
Verified
Journal Article
Open access
Rizwan QaisarRizwan Qaisar
Rizwan Qaisar
AKAsima Karim
Asima Karim
MIM. Shahid Iqbal
M. Shahid Iqbal
FAFirdos Ahmad
Firdos Ahmad
ASAhmad Shaikh
Ahmad Shaikh
NKNizar A. Khamjan
Nizar A. Khamjan
Postural dysfunction is a common problem in patients with Alzheimer's disease (AD) and may lead to functional dependency and increasing morbidity and mortality. However, the pathophysiology of postural dysfunction in AD patients remains poorly understood. Elevated intestinal permeability is an underlying contributor to multiple diseases, including AD. We aimed to investigate the association of elevated intestinal permeability with postural dysfunction in AD patients. We conducted a cross-sectional, observational study on older adults, including controls and AD patients. We investigated the associations of postural balance with plasma zonulin, a marker of elevated intestinal permeability in geriatric controls (n = 74) and patients with mild (n = 71) and moderate (n = 66) AD. We used a standardized physical performance battery to measure balance in supine, tandem, and semi-tandem positions. We also measured handgrip strength (HGS), and gait speed as markers of physical capacity. AD patients exhibited lower balance scores, HGS, and gait speed and higher plasma zonulin than in controls (all p < 0.05). Plasma zonulin levels demonstrated significant areas under the curves in diagnosing poor balance in AD patients (all p < 0.05). Moderate AD was associated with lower balance and physical capacity, and higher zonulin than mild AD (ALL P < 0.05). Poor scores on balance scale were associated with higher expressions of markers of inflammation, oxidative stress, and muscle damage providing a mechanistic link between increased intestinal permeability and postural dysfunction in AD patients. The results of our study show that plasma zonulin measurement may be used to diagnose postural dysfunction in AD patients. The study is relevant to non-ambulant and/or comatose AD patients with postural dysfunction. Our findings also highlight the therapeutic potential of repairing the intestinal leak to improve postural control and reduce the risk of falls in AD patients.

1 August 2025 in Journal of Pharmacology and Pharmacotherapeutics
Verified
Journal Article
Open access
SMSyam Mohan
Syam Mohan
NKNizar A. Khamjan
Nizar A. Khamjan
SASiddig Ibrahim Abdelwahab
Siddig Ibrahim Abdelwahab
MTManal Mohamed Elhassan Taha
Manal Mohamed Elhassan Taha
JMJobran M. Moshi
Jobran M. Moshi
TSTariq Idris Somily
Tariq Idris Somily
Background: Exosomes, key mediators of intercellular communication, transport functional biomolecules, making them promising tools for diagnostics and therapeutics across various human diseases. Objectives: To systematically review and analyze the clinical applications of exosomes, focusing on their sources, functions, therapeutic roles, and research trends through a bibliometric approach. Methodology: A comprehensive PubMed search was conducted using the term “exosomes” in titles and abstracts, limited to clinical studies, including Clinical Trials, Phase I–IV studies, and Randomized Controlled Trials. Ninety clinical trials were included. Bibliometric analysis using VOSviewer identified key terms, conceptual clusters, and emerging research topics. Results: Exosomes demonstrated diverse clinical applications in oncology, neurodegenerative diseases (e.g., Alzheimer’s), cardiovascular conditions, osteoarthritis, COVID-19, spinal cord injuries, transplant rejection, and skin regeneration. Predominant exosome sources included plasma, serum, urine, saliva, tears, ascites, adipose tissue, and stem cells. Functionally, exosomes served as diagnostic biomarkers, therapeutic agents, and molecular delivery systems. Key terms included miRNA, plasma, safety, efficacy, and trial, with conceptual clusters reflecting a shift from molecular exploration to clinical implementation. Emerging themes included precision medicine, biobank integration, and regenerative therapies using mesenchymal stem cell-derived or herbal-modified exosomes. Conclusion: Exosome-based interventions show promising safety and efficacy but face challenges in standardizing isolation methods, conducting large-scale randomized trials, and ensuring long-term follow-up. Future research should focus on integrating exosome platforms into precision medicine with robust clinical frameworks.